Protective helmet



FIG. 1 is a bottom, front and right-side perspective view of the protective helmet showing our new design;

FIG. 2 is a bottom, front and left-side perspective view thereof;

FIG. 3 is a bottom, rear and right-side perspective view thereof;

FIG. 4 is a bottom, rear and left-side perspective view thereof;

FIG. 5 is a top, front and right-side perspective view thereof;

FIG. 6 is a top, front and left-side perspective view thereof;

FIG. 7 is a top, rear and left-side perspective view thereof;

FIG. 8 is a top, rear and right-side perspective view thereof;

FIG. 9 is a right-side view thereof;

FIG. 10 is a front view thereof;

FIG. 11 is a left-side view thereof;

FIG. 12 is a rear view thereof;

FIG. 13 is a top view thereof;

FIG. 14 is a bottom view thereof;

FIG. 15 is a bottom, rear and right-side perspective view thereof, with the neck detail removed from FIG. 3;

FIG. 16 is a top, rear and left-side perspective view thereof, with the neck detail removed from FIG. 7;

FIG. 17 is a right-side view thereof, with the neck detail removed from FIG. 9;

FIG. 18 is a rear view thereof, with the neck detail removed from FIG. 12; and,

FIG. 19 is a bottom view thereof, with the neck detail removed from FIG. 14.

The details shown in broken lines in FIGS. 1 to 19 form no part of the claimed design. 

The ornamental design for a protective helmet, as shown and described. 